Body Mass Index and Mortality from Nonrheumatic Aortic Valve Disease among Japanese Men and Women

Aim: We aimed to examine the impact of overweight and obesity on mortality from nonrheumatic aortic valve disease. Methods: In the Japan Collaborative Cohort Study, we analyzed data of 98,378 participants aged 40–79 years, with no history of coronary heart disease, stroke, or cancer at baseline (1988–1990) and who completed a lifestyle questionnaire including height and body weight; they were followed for mortality until the end of 2009. The Cox proportional hazards model was used to calculate the multivariable hazard ratios (HRs) with 95% confidence intervals (CIs) of nonrheumatic aortic valve disease mortality according to body mass index (BMI) after adjusting for potential confounding factors. Results: During the median 19.2 years follow-up, 60 deaths from nonrheumatic aortic valve disease were reported. BMI was positively associated with the risk of mortality from nonrheumatic aortic valve disease; the multivariable HRs (95% CIs) were 0.90 (0.40–2.06) for persons with BMI ＜21 kg/m(2), 1.71 (0.81–3.58) for BMI 23–24.9 kg/m(2), 1.65 (0.69–3.94) for BMI 25–26.9 kg/m(2), and 2.83 (1.20–6.65) for BMI ≥ 27 kg/m(2) (p for trend=0.006), compared with persons with BMI 21–22.9 kg/m(2). Similar associations were observed between men and women (p for interaction=0.56). Excluding those who died during the first ten years of follow-up or a competing risk analysis with other causes of death as competing risk events did not change the association materially. Conclusions: Overweight and obesity may be independent risk factors for nonrheumatic aortic valve disease mortality in Asian populations.